Accessing symbols and special characters on a webOS phone was a simple task of just using the Sym or option (orange/silver) keys on the physical keyboard. Since the Touchpad and webOS 3.0 has replaced with physical keyboard with a virtual one, you need a different way of accessing these addition characters. There are three may ways of extending the functionality of the keyboard:

Just as on a computer's keyboard, the number row across the top contains some alternate symbols. Pressing the SHIFT (up arrow) key on the keyboard will allow you to access those symbols, as well as CAPS letter. You can either press the shift key and then the symbol, or you can press and hold the shift key and press multiple symbols. Note that the 4 grey key on the lower right (, . ' and -) also has alternate symbols

Press the key on the lower left to change each letter into an alternate character, as well as some smiley faces. To change back to letters, either tap that key again (which now says ABC) or press the space bar

You can also press and hold on almost and key to bring up other context-specific characters, just like holding down the keyboard key for different size keyboards. Any key that has additional characters will show an "..." on the bottom left of the key. And when the keyboard shows a ".COM" button, tapping that will also give you additional options like .net, .org and .edu. Once you have the pop-up with the additional character, you can either:

Tap on the character you want to insert it into your text

Tap another key with the "..." to see the characters for that key

Tap on the currently select key or any key without additional characters to dismiss the pop-up without inserting anything into your text